Stadium backers huddled inside a crowded tent Tuesday next to the Metrodome in downtown Minneapolis to break ground on the long-anticipated $975 million Vikings stadium. Excavation for the new 1.7 million-square-foot project started in earnest this week and is expected to wrap up in April.

The Nelson Cultural Center, scheduled to open June 30 after more than a year of construction, stands out on Park Avenue South as a modern companion to the historic Turnblad Mansion, the American Swedish Institute’s longtime home.